A leading Iranian newspaper has launched a competition asking people to submit cartoons about the Holocaust.

The Hamshahri daily says the competition is to test the boundaries of free speech for Westerners.

The move is seen as retaliation for the publication in a Danish paper of images satirising the Prophet Muhammad.

In a notice posted on its website, Hamshahri invited artists to send up to three cartoons by 5 May and promised to announce the results.

The Muhammad cartoons, published by the Jyllands-Posten in Denmark, have caused angry protests across the Muslim world.

One of the cartoons showed the Prophet Muhammad, whose image is banned in Islam, as a terrorist bomber.

Several European dailies republished the cartoons, citing freedom of speech.

'Unforgiven crime'

Hamshahri graphics editor, Farid Mortazavi, announcing the contest earlier this month, challenged Western newspapers to publish the Iranian cartoons as they did the European ones.

It's a bad reaction to a bad action coming from the Danish newspaper

Nik Kosar,former Hamshahri cartoonist

In its website notice, the Iranian daily called the competition, "What is the limit of Western freedom of expression?".

The newspaper said that Westerners used free speech to attack Muslim beliefs but did not permit debate on other subjects.

"This attack comes despite the fact that it is an unforgiven crime in the West to debate and critique many issues including the domineering system, looting and crimes perpetrated by the US and Israel, as well as alleged historical events like the Holocaust," the newspaper said.

Iran's hardline president, Mahmoud Ahmadinejad, has attracted international criticism for calling the Holocaust a "myth".

Hamshahri is going to measure the sanctity of freedom of expression among Westerners

Hamshahri

Vice-President of the World Jewish Congress Lord Greville Janner told the BBC he did not approve of the Danish cartoons and was not surprised that Muslims were upset, but he condemned the Iranian daily's competition.

"I think it is absolutely awful and I believe that that is no way we should be living in a decent world," he said.

Nik Kosar, a former cartoonist for Hamshahri, said he thought the competition was the wrong approach.

"It's a bad reaction to a bad action coming from the Danish newspaper," he told the BBC.